How do you solve #3secx-cosx-2=0# and find all solutions in the interval #0<=x<360#?

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Answer 1 · 2016-07-20T16:54:27

#3/cosx -cosx - 2 = 0#

#3/cosx - cos^2x/cosx - (2cosx)/cosx = 0#

#-cos^2x - 2cosx + 3 = 0#

#-cos^2x - 3cosx + cosx + 3 = 0#

#-cosx(cosx + 3) + 1(cosx + 3) = 0#

#(-cosx + 1)(cosx + 3) = 0#

#x = 0^@#

Also, beware that #x !=90^@ or 270^@#, since it would make the expression undefined.

Hopefully this helps!